Shelving units are commonly used for storing various items in a space-efficient manner. Typical shelving units may include four vertical supporting posts, any suitable number of horizontal front and corresponding horizontal rear shelf-supporting beams extending respectively between the front pair and rear pair of posts, and a corresponding number of shelves resting on and supported by the pairs of front and rear beams. Such shelving units may be constructed at least partially of sheet metal or formed steel components and are commonly referred to as steel shelving or storage units.
As loads are applied to such shelving units, such as by loading heavy items onto the shelves thereof, the front and rear horizontal beams are susceptible to undesirable twisting or torquing, in cross-section, out of their positions, particularly when strained beyond their capacity to remain in their design position. This twisting presents undesirable structural responses and could lead to shelving unit failure. For example, undue twisting of the front and rear horizontal shelf-supporting beams could separate the supporting inter-connection of the shelves to the beams, allowing the beams to pull away from the shelves thereby letting them drop, or could separate the beam ends from the corner posts thereby catastrophically destroying the shelving unit.
Some attempts have been made to address these issues by positioning a tie bar between each pair of horizontal front and rear horizontal shelf-supporting beams. For example, U.S. Pat. No. 9,375,102 discloses shelving units with such tie bars. However, prior art tie bars have a variety of drawbacks. For example, such tie bars offer no direct torque resistance to upper portions of the shelf-supporting beams of the shelving units. As a result, shelving units constructed with such tie bars continue to suffer from undesirably low load-bearing capacities.
It would therefore be desirable to provide tie members for shelving units that improve the structural integrity and load-bearing capacities of the shelving units.